Neo-Aortic Root Dilation in Pregnancy After Arterial Switch for Complete Transposition of the Great Arteries

Background The arterial switch operation (ASO) is standard treatment for D-transposition of the great arteries, and neo-aortic dilation is common afterward. Its behavior during pregnancy remains uncertain, especially the risk of dissection. Case We describe a 30-year-old woman (G6P0A5) with neo-aortic dilation (44 mm) during her first pregnancy, which remained stable on beta blockers until an uncomplicated caesarean delivery. In her subsequent pregnancy, an initial measurement of 47 mm raised concern. Expert review highlighted the challenges of accurately measuring asymmetric neo-aortas post-ASO and confirmed that the neo-aorta was stable (43 mm). The pregnancy continued without complications under beta-blocker therapy. Discussion No neo-aortic dissections have been reported after ASO, and progression above 2 mm was reported only in a few (2/131). Preconception evaluation, standardized measurement techniques, and trimester-based surveillance are essential. Mode of delivery should be individualized; caesarean delivery may be reasonable when dilation exceeds 45 mm.